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 A046107 Triangle of prime numbers in which n-th row lists all primes p such that 1/p has decimal period n, n >= 1. 13
 3, 11, 37, 101, 41, 271, 7, 13, 239, 4649, 73, 137, 333667, 9091, 21649, 513239, 9901, 53, 79, 265371653, 909091, 31, 2906161, 17, 5882353, 2071723, 5363222357, 19, 52579, 1111111111111111111, 3541, 27961, 43, 1933, 10838689, 23, 4093 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The number of numbers in each row n is given by A112505(n). In the 18th century, the Japanese mathematician Ajima Naonobu (aka Ajima Chokuyen) gave the terms through 5882353 (Smith and Mikami, p. 199). - Jonathan Sondow, May 25 2013 REFERENCES Ajima Naonobu (aka Ajima Chokuyen), Fujin IsshÅ© (Periods of Decimal Fractions). LINKS Ray Chandler, Rows n=1..322, flattened (first 276 rows from T. D. Noe) David Eugene Smith and Yoshio Mikami, A History of Japanese Mathematics, Open Court, Chicago, 1914; chapter X. Eric Weisstein's World of Mathematics, Decimal Expansion. EXAMPLE First rows of irregular triangle are: 3; 11; 37; 101; 41, 271; 7, 13; 239, 4649; 73, 137; 333667; 9091; 21649, 513239; 9901; 53, 79, 265371653; 909091; 31, 2906161; 17, 5882353; ... MATHEMATICA pp={}; Do[f=Transpose[FactorInteger[10^n-1]][[1]]; p=Complement[f, pp]; pp=Union[pp, p]; Print[p], {n, 66}] (* T. D. Noe, Sep 08 2005 *) CROSSREFS Cf. A007138 (first column). Sequence in context: A095088 A306362 A007138 * A243110 A061075 A005422 Adjacent sequences:  A046104 A046105 A046106 * A046108 A046109 A046110 KEYWORD nonn,tabf,base AUTHOR STATUS approved

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Last modified March 29 21:32 EDT 2020. Contains 333117 sequences. (Running on oeis4.)